Process for obtaining a sponge-textured thread from natural silk thread

ABSTRACT

Sponge-textured thread is made from natural silk thread by subjecting the silk thread to conventional degumming operations, then to known operations of the conventional method of obtaining a sponge-textured thread; i.e., twisting, fixing by thermal or steam treatment and untwisting, and then placing the silk thread in a humid medium, which is preferably hot. If the humid treatment is effected after weaving or knitting, these must be very loose. After the degumming step the silk thread can be coupled to another thread of silk or other fiber.

United States Patent Hilaire 1451 June 6, 1972 54] PROCESS FOR OBTAINING A SPONGE- 2,029,969 2 1936 Wallerstein et 211.. ..28/60 TEXTURED THREAD FROM NATURAL 2,127,904 8/1938 Chamberlin ...28/60 SILK THREAD 2,451,919 10/1948 Clarks0n..... .57/156 3,085,390 4/1963 Dubini. ...57/34 Inventor: Marcel Marius A n Hilaire, 3,091,913 6 1963 Field .57 140 deche, France 3,289,401 12 1966 Gliksmann et al. ..57 157 [73] Assignees Societe Forezienne de Moulinage et Textu- 3355785 12/1967 Barber 5 7/ l5 7 X ration, Loire, France 3,412,543 11/1968 Horvath ..57/34 3,526,084 9/1970 London at al ..57 157 x [22] Filed: Sept. 25, 1969 [30] Foreign Application Priority Data Sept. 25, 1968 France ..6850428 [52] .U.S.Cl ..57/156 [51] Int. Cl ..D02g 3/04, D03d 15/00 [58] Field ofSearch ..57/34 HS, 139, 140, I56, 157; 28/60 [56] References Cited UNITED STATES PATENTS 2,025,989 12/1935 Kaplan ..28/60 Primary ExaminerDonald E. Watkins Attorney-Waters, Roditi, Schwartz & Nissen [57] ABSTRACT Sponge-textured thread is made from natural silk thread by subjecting the silk thread to conventional degumming operations, then to known operations of the conventional method of obtaining a sponge-textured thread; i.e., twisting, fixing by thermal or steam treatment and untwisting, and then placing the silk thread in a humid medium, which is preferably hot. If

the humid treatment is effected after weaving or knitting, these must be very loose. After the degumming step the silk thread can be coupled to another thread of silk or other fiber.

8 Claims, No Drawings PROCESS FOR OBTAINING A SPONGE-TEXTURED THREAD FROM NATURAL SILK THREAD The present invention relates to a process for obtaining a sponge-textured thread from natural silk thread.

After the appearance of synthetic threads which do not have any natural elasticity, research was directed towards the obtaining of a sponge (or foam )-textured thread by reason not only of the improvement of their calorific qualities, but also of the greater ease of adaptation to the user of articles woven or knitted by means of these threads.

Several methods have been applied for obtaining spongetextured thread starting from synthetic thread, but none of them is applicable to silk thread. This is especially the case for the conventional method of obtaining sponge-textured thread, which consists of subjecting the thread to twisting, fixing by thermal or steam treatment and substantial untwisting equal and in opposite direction to the twisting. This method applied to silk thread procures for it practically no elasticity.

It is an object of the present invention to overcome this lack.

According to the invention, there is provided a method for obtaining sponge-textured thread from natural silk thread, said method consisting of subjecting the silk thread, after the conventional operations of degumming, to the known operations of the conventional method of obtaining a sponge-textured thread, that is to say twisting, fixing by heat or steam treatment, untwisting, then of placing this thread, before or after weaving or knitting, in a humid medium and preferably hot.

This latter operation has established that it gives silk thread a spongy texture as a result of its inflation which results from its passage in the humid medium, while the aforesaid conventional method alone had left it practically inert.

Naturally, in the case where the moisture treatment is effected directly, after untwisting, but before weaving or knitting, it is necessary that the thread be introduced on floats" or cakes. In the case where the moisture treatment is effected after weaving or knitting, the latter must be effected very loosely.

In this last case, the silk thread with one or several ends which have undergone after S untwisting (to the right) or Z (to the left) fixing and untwisting, can be used alone or coupled or bound to another silk thread having undergone the same inverse Z or S operation or to any other thread of natural or synthetic fiber, direct from spinning or textured.

In addition, the silk thread can be bound by slight torsion, to a thread of another nature with standing twisting, before the application of the conventional method of obtaining a spongetextured thread, that is to say, immediately after degumming.

Preferably, the operation of degumming which the natural silk thread must necessarily undergo to be freed from the gum with which it is naturally impregnated,'is carried out after having given a slight twisting of, for example, 300 turns S or 2 per meter. Thus degumming does not risk involving welding together the various turns of the thread.

The conventional operation of twisting, fixing and untwisting, consists, for example, of making the silk thread undergo twisting of 2,000 to 5,000 turns per meter, to fixing at a temperature which can go up to C, then of untwisting as close as possible to the zero point.

As goes without saying, the invention is not limited to the single embodiment of this method which has been described above, by way of non-limiting example, it embraces, on the contrary, all variations of realization.

I claim:

1. In a method of obtaining sponge-textured thread from natural silk thread, including degumming said silk thread, twisting said thread, thermally fixing said thread, and untwisting said thread, the improvement comprising; positioning said thread in a humid medium so as to expand the thread to its sponge texture.

2. A method according to claim 1, wherein said humid medium is hot.

3. A method according to claim 1, wherein the humid treatment is eifected directly after the said untwisting of the thread and the thread is introduced on support means.

4. A method according to claim 1 wherein the humidity treatment is effected after loosely weaving or knitting said thread into a fabric.

5. A method according to claim 1, wherein the silk thread includes at least one end which has undergone S or Z twisting, fixing and untwisting and is coupled or bound to another thread having undergone the same reverse 2 or S operation, direct from spinning.

6. A method according to claim 1, wherein the operation of degumming is effected after giving said thread a slight torsion of 300 turns S or Z per meter.

7. A method according to claim 1, wherein said operation of twisting, fixing and untwisting consists of subjecting the silk thread to twisting of 2,000 to 5,000 turns per meter, fixing, then of untwisting as close as possible to the zero point.

8. A method according to claim 1, wherein the silk thread is bound by slight twisting, to a further thread having a characteristic of withstanding the twisting, prior the application of the humid medium-preceding steps of obtaining a sponge-textured thread. 

2. A method according to claim 1, wherein said humid medium is hot.
 3. A method according to claim 1, wherein the humid treatment is effected directly after the said untwisting of the thread and the thread is introduced on support means.
 4. A method according to claim 1 wherein the humidity treatment is effected after loosely weaving or knitting said thread into a fabric.
 5. A method according to claim 1, wherein the silk thread includes at least one ''''end'''' which has undergone S or Z twisting, fixing and untwisting and is coupled or bound to another thread having undergone the same reverse Z or S operation, direct from spinning.
 6. A method according to claim 1, wherein the operation of degumming is effected after giving said thread a slight torsion of 300 turns S or Z per meter.
 7. A method according to claim 1, wherein said operation of twisting, fixing and untwisting consists of subjecting the silk thread to twisting of 2,000 to 5,000 turns per meter, fixing, then of untwisting as close as possible to the zero point.
 8. A method according to claim 1, wherein the silk thread is bound by slight twisting, to a further thread having a characteristic of withstanding the twisting, prior the application of the humid medium-preceding steps of obtaining a sponge-textured thread. 